Novel fabrication perspectives have been demonstrated to molecularly construct robust hollow fiber membrane supports for high performance thin-film-composite (TFC) pressure retarded osmosis (PRO) membranes. For the first time, we found that the desirable hollow fiber supports should possess high stretch resistance and acceptable ductility. The micro-structure strength of the hollow fiber support may have more weights on overall robustness of the TFC PRO membranes than the apparent cross-section morphology. Effectively manipulating the kinetics of phase inversion during spinning by maneuvering bore fluid chemistry and polymer solution composition is a promising method to tailor the strength of hollow fiber supports. Pre-stabilization of the TFC membranes at elevated lumen pressures can significantly improve their PRO performance. The newly developed TFC PRO hollow fiber membranes exhibit a power density as high as 16.5 W/m2 and a very low specific reverse salt flux (Js/Jw) of 0.015 mol/l at a hydraulic pressure of 15 bar using synthetic seawater brine (1.0 M NaCl) as the draw solution. © 2013 American Institute of Chemical Engineers AIChE J, 2013